A combination of measurement and control techniques is being increasingly used in the oil industry to capture fluid dynamics in the far-field (several meters) of well bores as it has the potential to significantly improve oil and gas production. This is due to the recent development of oil well technology which allows zonal production control and monitoring in real time through respectively, inflow control valves and down hole sensors. Inflow control valves are capable of imposing a pressure profile along the well that can influence the flow behavior. The advantage of this type of proactive control is that potential problems such as the approach of unwanted fluids or migration of wanted fluids toward production wells can be mitigated before they impact production. The efficiency of these strategies is based on the capacity of measuring or predicting changes in the reservoir away from the well bore.
The presence of an enormous volume of potentially recoverable gas in shale rock in the United States (e.g., Marcellus shale gas) has a great economic significance. This will be some of the closest natural gas to the high population areas of New Jersey, New York and New England. This transportation advantage will give Marcellus shale gas a distinct advantage in the marketplace. Natural gas occurs within Shale rock in three ways: 1) within the pore spaces of the shale; 2) within vertical fractures (joints) that break through the shale; and 3) adsorbed on mineral grains and organic material. Most of the recoverable gas is contained in the pore spaces. However, the gas has difficulty escaping through the pore spaces because they are too small, poorly connected, or non-existent to provide gas recovery pathways
Removal or desorption of natural gas in rock formations using radiofrequency energy occurs by two basic mechanisms: (1) the molecular vibration of gas molecules attached to shale surfaces interacting with the radiofrequency electric fields and (2) the expansion of and increased interconnected micro cracks of rock by heating connate water or fossil water to create enhanced rock permeability for gas recovery. Localized expansion of pore water in rock to create micro fracturing is based on the radiofrequency heating of pore water to create high vapor pressures. No injected water or chemicals is required.
Detailed information on fracture network architecture greatly assists in the recovery of gas and oil in rock or other tight formations through location of existing pathways for gas flow or oil vapor recovery. Positioning of RF high power antennas in the vicinity of fractures allows for increased gas flow derived from desorption or chemical pyrolysis using electromagnetic energy of appropriate frequency and intensity as well as providing fracture network enhancement through RF heating through steam generation. No water injection or chemical injections are required.
Removal of many pollutants or toxic material is especially difficult when the contaminants enter bedrock fractures. For example, The heterogeneous distribution of residual 1,1,1-trichloroethane (TCA) dense nonaqueous phase liquid (DNAPL) within discrete, poorly connected bedrock fractures renders many remedial technologies inefficient or ineffective because the DNAPL cannot be physically removed or reached to treat in situ. Thermal resistivity heating and thermal conduction heating can treat a targeted volume of bedrock, overcoming the physical constraints of the bedrock fracture network, but can be prohibitively expensive to implement due to energy requirements for heating the rock mass. Thus, a system and method that facilitates the removal of such pollutants from bedrock fractures would be beneficial.